Gate-valve



(N0 ModeL) H1 LIBBEY,

GATE VALVE.

No. 577,924. Patented Ma 2, 1897.

arm,

Wit 55.

NlTED STATES I l ATENT OFFICE.

GATE-VALVE.

SPECIFICATION forming part of Letters Patent No. 577,924, dated March 2,1897. Application filed Tune 20, 1896. Serial No. 596,260. (No model.)

To all whom it may concern.-

Be it known that I, HENRY N. LIBBEY, a citizen of the United States, anda resident of Boston, in the county of Sulfolk and State ofMassachusetts, have invented new and useful I1nprovements inGate-Valves, of which the following, taken in connection with theaccompanying drawings, is a specification.

This invention relates to improvements in gate-valves for steam andliquids; and it has for its object to permit the steam or liquid in theoutlet end to escape freely when the valve is closed, which is verydesirable in case of repairs to the pipes beyond the valve or for thepurpose of preventing the liquid in the pipe from freezing in coldweather, as will hereinafter be more fully shown and described,reference being had to the accompanying drawings, wherein- Figure 1represents an end view of the improved valve, showing its gate closed.Fig; 2 represents a vertical section on the line 2 2 in Fig. 1, showingthe gate closed. Fig. 3 represents a similar vertical section showingthe gate open. Fig. 4. represents a cross-section on the line 4 4 shownin Fig. 2. Fig. 5 represents a detail side view of the gate or plug, andFig. 6 represents an end view of said gate or plug.

Similar letters refer to similar parts wherever they occur on thedifferent parts of the drawings.

In the drawings, A represents the valveshell having supply branch B anddelivery branch 0, as shown.

Band O are perforated valve-seats at the inner ends of the respectivebranch B and 0. Below the said branches B O the valve-shell is extendedas a chamber A, to which is detachably secured the screw-threadedperforated cap or cover D, as shown. Centrally within the valve-shell islocated the longitudinally-adjustable tapering gate or plug E, having atransverse perforation E, coinciding, or nearly so, with theperforations h c in the valve-seats B 0 when the valve is open, as fullyshown in Fig. 3.

The plug or valve E is guided in a suitable manner within the shell Aand is operated up and down within said shell by means of ascrew-threaded valve-spindle F, journaled in the upper end of said shelland provided at its upper end with a suitable hand-wheel f, as is commonin devices of this kind.

G represents the gland, and H the stuffingboX for the valve-spindle, asusual.

6 is a perforation at one side of the valve or plug E for the purpose ofletting out the Water from the branch 0 and pipes connected thereto whenthe valve is closed, as shown in Fig. 2.

The cap D has an upward1y-projecting valve-stem I), provided with acentral discharge-opening d, as shown in Figs. 2 and 3-.

The valve or plug E is provided with a recess E on its under sideadapted to receive the stem D when the valve is open, as shown in Fig.3. In the bottom of said recess E is a leather or equivalent valve-seat6, adapted to close against the upper end of the hollow stem D when thevalve is open, as shown in Fig. 3.

The operation is as follows: The valve is opened by moving the plug Edownward, as

shown in Fig. 3, when communication is established between the branchesB and O, and during such position of the said plug the vent d is closedby the valve 6 being forced against the upper end of the hollow stem D,as shown in said Fig. 3. When the plugE is raised up ward and closedagainst the valve-seats B O, the exhaust d is in open communication withthe branch 0 by means of the valve-perforation 6, as shown in Fig. 2,thus permitting the liquid or back pressure in the branch 0 and pipesconnected thereto to escape through the port a and the perforation d inthe stem D, as fully represented in Fig. 2.

Having thus fully described the nature, construction, and operation ofmy invention, I wish to secure by Letters Patent and claim In agate-valve having supply and delivery branches and valve-seats thereoncombined with a perforated adjustable plug having an exhaust-port incommunication with the delivery branch, a Valve-seated recess in theunder side of said plug and a hollow stem in the name to thisspecification, in the presence of lower portion of the valve-shell, saidstem havtwo subscribing Witnesses, on this 20th day of ing anexhaust-vent and having its upper end May, A. D. 1896.

adapted to be closed against the valve-seated HENRY N. LIBBEY. 5 recessin the p1u g substantially as and for the Witnesses:

purpose set forth. ALBAN ANDRB'JN,

In testimony whereof I have signed my GEORGE C. WHORF.

